Problem with unloading images

Hi, in short I can load image in MC. But when I try to unload, happened problem. Image stay there. Why I’m mistaken?

Here is my AS
[AS]
import flash.display.Loader;

var bigOne_loader:Loader = new Loader();
show_btn.addEventListener(MouseEvent.MOUSE_DOWN, showMeBigOne);

function showMeBigOne(info:MouseEvent):void {
bigOne_loader.unload();

}

bigOne_loader.contentLoaderInfo.addEventListener(Event.COMPLETE, showPic_complite);
bigOne_loader.load(new URLRequest(“gallery/blah_blah.jpg”));

[/AS]